This proposal provides central support for Research in Mental Retardation at UCLA. The Mental Retardation Research Center at UCLA is a multi-funded, interdisciplinary research and teaching program which has the following objectives: 1. Research into problems of mental retardation and related aspects of human development. 2. Research training, at the pre- and post-doctoral levels, of specialists in a variety of disciplines related to our goals. Studies fall into the following categories: Developmental Biology, Neurophysiology, Neurobiochemistry and Socio-Behavioral Research. Most of our research efforts are carried out on the UCLA campus. Additionally, a large multi-disciplinary research program exists at the Pacific State Hospital (recently re-named Lanterman State Hospital) in Pomona, California.